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CS 17 mast step helper


Jim Stumpf

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Hello All,

Its been a couple of years since I checked in. This will be the my 9th season with my CS and I am thinking about an easier way to step the mast (more the main and not as much the mizzen). Lifting the mast strait up and dropping it into the step while standing on the fore deck becomes less safe each year and I am not interested in modifying the fore deck and installing a well with a pivoting tabernacle.  In years past I have seen some of the deck mounted guides and was kicking that idea around when my very creative boat building buddy had this idea, he didn't have all of the details in his head but when searching the web we stumbled across this picture on Russ Livingstone's web site. All though not exactly what we need the concept is there. A small knuckle at the bottom of the mast  to catch the top of mast tube and guide the mast into the tube as it is being pivoted/lifted and would drop into the mast tube. Any thoughts on the idea would be greatly appreciated. 

 

As always thanks in advance for your help.

CCI24042015 - Copy.jpg

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Jim — Have a look at my posting for June 13, 2017, on “Chessie’s” build and the various replies posted by members and myself.  CORRECTION, I made a posting on June 13, 2017, but it wasn’t on “Chessie’s” build.  It was on someone else’s build.  You can find it by searching “stepping aid” on this forum.

 

The little gadget described in that posting has worked well for me.  The 22 lb mast weight isn’t the problem — it’s the unsteadiness!  Once one gets the mast heel in (or close to) that funnel-like cup, then one feels much more in control for the rest of the job.

 

And I like the concept in the photo you posted.  I think it might just work quite well.  The stub heel of the mast should be as short as possible [for its purpose of getting the mast heel (just) into its partner] — so that when fully into the partner, the distance from the pivot to the underside of the mast partner is as long as possible — keeping the leverage on the pin and heel stub to a minimum.  You didn’t mention it, but the mast needs to be held upright after stepping while someone (you or crew) inserts the pin.

 

Good luck!  I’d like to see your final decision.

 

Here are a few photos of my stepping aid:

6861E041-199E-4AEF-AE79-AE259CA8AC78.thumb.jpeg.0f70915e3aed34b95025bf92cf481402.jpeg

B793BBD0-98D7-4F51-97B5-D56BBF02D413.thumb.jpeg.b39c52a56abcf6825618995a174956ce.jpeg

05359457-BCD9-48E9-85D1-8B2A834DBFAD.thumb.jpeg.3b268a3118f628c60f0efb8bbeb7b3a3.jpeg

5D3CBC09-4319-40E5-96F0-4AEB8DF69704.thumb.jpeg.125368fc09ae3e3097042635ef176e32.jpeg

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I left the front edge of my tube a little long, sticking up.  The shape is something like Pete's, but not as tall, and it's permanent.  It provides enough to put the heel of the mast against and push.  Works swell.  Sorry I don't have a picture.  Probably too late for Jim now, anyway, since I assume his tube is cut flush.  But, thought I would mention.

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Thanks for the replies.

Pete your pics are similar to where we started and may end up. In the concept picture in my post there would be no need for the lock pin as the whole assembly would drop into the mast tube and be captured in an upright position. The pictured application from my orginal post looks like it was a deck step with out the support of the mast tube. If applied to my application I do have a concern about the compression forces on the pivot of the knuckle, it would have to pretty robust to stand up the force applied by sailing with out distorting the  knuckle.

 

Paul is right that I ended my tube at the deck years ago.

 

Jim

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Hola All,

 While in lock down mode I too have been working on my answer for the mast stepping issue. My cabin makes it a little more difficult than planned to get solid footing so I wanted a way to use both what was already there, and some "mechanical" advantage for the hoist.

I  decided to use up what was here and make my own tabernacle that would;

1. Allow me to set the foot of the mast into a socket

2. Do the hoist/lowering with the help of my double topping lifts, and the bow roller.

3. Allow the original MK1 design of a rotating mast to STILL function

4. Be removable if i wanted to clear the deck a bit.

Made the "cheeks(?)" out of some Padauk I had stashed from her build days, and then took some PVC pipe, a brass piano hinge, and a few large SS bolts to fab it up. Rigged a "tab"on the bottom of the PVC step to both clear my bow cleat, and also to  "stop" the hoist when it came into contact with the stub of the mast tube I had left protruding.

Once raised I can simply lift the PVC out of the notches on the cheeks, and store it until/if I need it to unstep the main mast. I have only used it a few times so far, but it works well and when we are allowed near the water again I hope to give it a try while on her trailer at the launching beach. report will (eventually) follow.

PS- Mast float project is also on hold as I can't even get to the beach to float test the rig.

 

Paduak-cheeks.jpg

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outside-counter.jpg

MS-notch.jpg

MS-notch-2.jpg

MS-1.jpg

MS-lowered.jpg

step-in-place.jpg

topping-lift-angle.jpg

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Thanks for sharing your design. I like it.

Two questions

1. is there a stop to keep the mast from passing through the bottom of your PVC tube before the mast is more or less vertical and ready to drop into the mast tube? Do you regulate the depth manually to keep the mast from contacting the deck?

2. In hind site do you think the tabernacle could have been scaled down or are you finding the forces involved warrant the scale. I ask this question with all due respect.

 

Thanks, Jim

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Jim,

I have been playing with the stop concept and trying to rig a little "tab" I can move to create a "temporary bottom"  of the PVC tube until I get it upright. So far I have just rested the mast bottom on the lip of the Carbon fiber deck tube ,and with the "stop"on the forward face of the PVC I can keep it in place while under control, and then just lower it all the way.

I used such tall/large pieces for the cheeks because my trunk cabin height ( see attached)  would not allow me to start from a fully horizontal position if it was shorter. At this height I can lay the mast flat on the cabin before I start the hoist. And since this is really the prototype design I always go larger, as it's easier to scale back...

PS- The design as shown above does not close completely around the mast so the sail track is not interfered with while lowering it into the deck tube....

head-room-2.jpg

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  • 3 weeks later...

The mast in that Ross Lillistone photo is a stayed mast.  Since the Core Sound masts are unstayed, all the energy produced by the sail is focused on the hull at the mast step.  I’d have grave concerns about using this tabernacle on an unstayed mast.  For our boats, there needs to be about 12” between the pivot and locking pin, not the 1.5” in the Lillistone design (for a stayed mast).  Plus, the tabernacle itself needs to be a robust design, capable of handling all these stresses.  A tabernacle is a great idea, when properly designed. 

10843B62-56BF-46D7-8275-698211F685E5.jpeg

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Thanks for the input, the thought was to use the knuckle to start the mast into the tube and then guide it down as you lift, so that the hinge would be contained in the lower mast tube when the mast is fully raised.  I agree that there would be no way to use it as a tabernacle without a stayed mast.

 

Thanks

 

Jim

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Another thought:  the really hard part is getting the mast out, after sailing.  A mast rest or the hinged device you're looking at in the original post will help you get it in and hoisted, but won't help much in pulling it out.  Absent a tabernacle of some sort, unstepping is pretty much a brute force job.  I get on the deck, pull up, balance the mast (and me!) when it comes out, let it slide down toward the water (still mostly vertical) until I reach a balance point when I can safely turn it horizontal and then finally lay it back. I feel like a Wallenda.  I agree with Don that any tabernacle on a CS still needs to allow for the mast foot to be buried the 12" or more in the plans.  Graham and Alan have developed some tabernacle options.  It might be best to look at them.  It's definitely a sticking point on the CS.

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DOH,  that is way I post here, it is always good to have a fresh prospective. I was so fixated on raising the mast I hadn't gotten to taking it back down again, that is very accurate that once the mast leaves the tube when taking down it can be unwieldy. I have been swayed that the knuckle idea should be abandoned. I guess it was a knuckle headed idea.

 

 

Thanks,

 

Jim

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